Discovery of variable VHE gamma-ray emission from the binary system 1FGL J1018.6-5856

Abramowski A, Aharonian F, Benkhali FA, Akhperjanian AG, Anguener EO, Backes M, Balzer A, Becherini Y, Tjus JB, Berge D, Bernhard S, Bernloehr K, Birsin E, Blackwell R, Boettcher M, Boisson C, Bolmont J, Bordas P, Bregeon J, Brun F, Brun P, Bryan M, Bulik T, Carr J, Casanova S, Chakraborty N, Chalme-Calvet R, Chaves RCG, Chen A, Chretien M, Colafrancesco S, Cologna G, Conrad J, Couturier C, Cui Y, Davids ID, Degrange B, Deil C, Dewilt P, Djannati-Atai A, Domainko W, Donath A, Drury LO, Dubus G, Dutson K, Dyks J, Dyrda M, Edwards T, Egberts K, Eger P, Ernenwein JP, Espigat P, Farnier C, Fegan S, Feinstein F, Fernandesl MV, Fernandez D, Fiasson A, Fontaine G, Foerster A, Fuessling M, Gabici S, Gajdus M, Gallant YA, Garrigoux T, Giavitto G, Giebels B, Glicenstein JF, Gottschall D, Goyal A, Grondin MH, Grudzinska M, Hadasch D, Häffner S, Hahn J, Hawkes J, Heinzelmann G, Henri G, Hermann G, Hervet O, Hillert A, Hinton JA, Hofmann W, Hofverberg P, Hoischen C, Holler M, Horns D, Ivascenko A, Jacholkowska A, Jahn C, Jamrozy M, Janiak M, Jankowsky F, Jung-Richardt I, Kastendieckl MA, Katarzynski K, Katz U, Kerszberg D, Khelifi B, Kieffer M, Klepser S, Klochkov D, Kluzniak W, Kolitzus D, Komin N, Kosack K, Krakau S, Krayzel F, Krueger PP, Laffon H, Lamanna G, Lau J, Lefaucheur J, Lefranc V, Lemiere A, Lemoine-Goumard M, Lenain JP, Lohse T, Lopatin A, Lu CC, Lui R, Marandon V, Marcowith A, Mariaud C, Marx R, Maurin G, Maxted N, Mayer M, Meintjes PJ, Menzler U, Meyer M, Mitchell AMW, Moderski R, Mohamed M, Mora K, Moulin E, Murach T, De Naurois M, Niemiec J, Oakes L, Odaka H, Oettl S, Ohm S, De Ona Wilhelmi E, Opitz B, Ostrowski M, Oya I, Panter M, Parsons RD, Arribas MP, Pekeur NW, Pelletier G, Petrucci PO, Peyaud B, Pita S, Poon H, Prokoph H, Pühlhofer G, Punch M, Quirrenbach A, Raab S, Reichardt I, Reimer A, Reimer O, Renaud M, De Los Reyes R, Rieger F, Romoli C, Rosier-Lees S, Rowell G, Rudak B, Rulten CB, Sahakian V, Salek D, Sanchez DA, Santangelo A, Sasaki M, Schlickeiser R, Schuessler F, Schulz A, Schwanke U, Schwemmer S, Seyffert AS, Simoni R, Sol H, Spanier F, Spengler G, Spies F, Stawarz L, Steenkamp R, Stegmann C, Stinzing F, Stycz K, Sushch I, Tavernet JP, Tavernier T, Taylor AM, Terrier R, Tluczykont M, Trichard C, Valerius K, Van Der Walt J, van Eldik C, Van Soelen B, Vasileiadis G, Veh J, Venter C, Viana A, Vincent P, Vink J, Voisin F, Voelk HJ, Vuillaume T, Wagner SJ, Wagner P, Wagner RM, Weidinger M, Weitzel Q, White R, Wierzcholska A, Willmann P, Wörnlein A, Wouters D, Yang R, Zabalza V, Zaborov D, Zacharias M, Zdziarski AA, Zech A, Zefi F, Zywucka N (2015)


Publication Language: English

Publication Status: Published

Publication Type: Journal article, Original article

Publication year: 2015

Journal

Publisher: EDP Sciences

Book Volume: 577

Pages Range: A131

Article Number: A131

DOI: 10.1051/0004-6361/201525699

Abstract

Re-observations with the HESS telescope array of the very high-energy (VHE) source HESS J1018-589A that is coincident with the Fermi-LAT gamma-ray binary 1FGL J1018.6-5856 have resulted in a source detection significance of more than 9 sigma and the detection of variability (chi(2)/nu of 238.3/155) in the emitted gamma-ray flux. This variability confirms the association of HESS J1018-589A with the high-energy gamma-ray binary detected Fermi-LAT and also confirms the point-like source as a new VHE binary system. The spectrum of HESS J1018-589A is best fit with a power-law function with photon index Gamma = 2.20 +/- 0.14(stat) +/- 0.2(sys). Emission is detected up to similar to 20 TeV. The mean differential flux level is (2.9 +/- 0.4) x 10(-13) TeV-1 cm(-2) s(-1) at 1 TeV, equivalent to similar to 1% of the flux from the Crab Nebula at the same energy. Variability is clearly detected the night-by-night light curve. When folded on the orbital period of 16.58 days, the rebinned light curve peaks in phase with the observed X-ray high-energy phaseograms. The fit of the HESS phaseogram to a constant flux provides evidence of periodicity at the level of N-sigma > 3 sigma. The of the VHE phaseogram and measured spectrum suggest a low-inclination, low-eccentricity system with a modest impact from VHE gamma-ray due to pair production (tau less than or similar to 1 at 300 GeV).

Authors with CRIS profile

How to cite

APA:

Abramowski, A., Aharonian, F., Benkhali, F.A., Akhperjanian, A.G., Anguener, E.O., Backes, M.,... Zywucka, N. (2015). Discovery of variable VHE gamma-ray emission from the binary system 1FGL J1018.6-5856. Astronomy & Astrophysics, 577, A131. https://doi.org/10.1051/0004-6361/201525699

MLA:

Abramowski, A., et al. "Discovery of variable VHE gamma-ray emission from the binary system 1FGL J1018.6-5856." Astronomy & Astrophysics 577 (2015): A131.

BibTeX: Download